66 Roadster - No numbers on pad? Broach marks look good. What's up?

[Robert W.]

I have been searching for a nice 65-67 Roadster with real "Born" matching numbers for the past 4-5 months. This is not a easy thing to do for a novice (NCRS and members have been most helpful). Most dealers use the phase "Matching Numbers" which pretty much means they have a re-stamped pad. Anyway, this has been a fun but serious learning trip.
Today I go look at a 66 white/red 350 hp Roadster. The first thing I look at is a pad without numbers. I wipe my eyes a couple of times and look again to see the same no numbers pad. The pad appears to have good broach marks with normal dirt and dry rust here and there on it (photo enclosed).
I know the owner at an arms-length and would like to give them an honest answer why their engine has a blank pad. I have heard of Target engines, but I would think these would have some sort of numbering system on them. Perhaps some Target engines got shipped without numbers as a mistake?
Any help would be appreciated.
Thanks
Bob Wingate (Dallas)

[Michael G.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

There would appear to be the remnants of several characters of the vin stamp on the extreme passenger's side of the pad...

[Gene M.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

There would appear to be the remnants of several characters of the vin stamp on the extreme passenger's side of the pad...

Mike has something there. Blow it up and you will see some remains of numbers.

[Michael W.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

I know the owner at an arms-length and would like to give them an honest answer why their engine has a blank pad. I have heard of Target engines, but I would think these would have some sort of numbering system on them. Perhaps some Target engines got shipped without numbers as a mistake?

I don't see any broach marks of any type. Possibly just a low-res pic.

Factory replacement engines of the era may/may not have had a stamped pad. Did you check the casting number and date of the engine case? 'Target' engines are a modern day product.

[Edward J.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

Bob, GM use to make over the counter engine blocks with no stamps with the broaching present. maybe this is what you have. Checking the casting date on back of block to see just how close this is to the production date, maybe this will give you and us some more info.

[Bill W.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

Bob,
My eyes are no longer good enough to tell if there is anything there or not. Check the casting date on the bell housing flange, passenger side. It should be close to May 20, 1966 (E206) also take a look at the casting number, it should end in numbers (174). This info should give you some idea what you are looking at.
Another possibility is the original motor was replaced at some point with a motor that was never stamped, as in came from a boat or was built to power an irrigation pump. Let us know what you find. Bill

[Robert W.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

I looked again and I can't see any numbers. I had a mechanic that was nearby look at the actual pad and he also could not see any numbers present. He also knew of Target engines.

[Michael G.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

Near the right edge of this pic, just below the chamfered corner of the pad, where you'd expect to find the first number of the vin derivative, there seems to be the bottom curve of a "3" or maybe a "6" or "5", then perhaps the top of an "8" on its left, then something else. The font looks right. No idea what these mean...

Screen Shot 2015-11-18 at 5.24.19 PM.png

On the left, there seems to something else, but its been obliterated by rust pits. Those pits look too uniform in size, like maybe they were the result of a punch or something.

[Joe R.]

Re: 66 Roadster - No numbers on pad? Broach marks look good. What's up?

Just one of many GM blocks that has been exposed to the elements, salt, rain, dirt and has rusted the numbers off the block. If the head is removed you will find the broach marks like new under the gasket.

JR